Add event dispatcher (#411)

Author: kristijanhusak

lua/orgmode/events/init.lua

@@ -0,0 +1,44 @@
+local Events = require('orgmode.events.types')
+local Listeners = require('orgmode.events.listeners')
+
+---@class EventManager
+local EventManager = {
+  initialized = false,
+  _listeners = {},
+  event = Events,
+}
+
+---@param event Event
+function EventManager.dispatch(event)
+  if EventManager._listeners[event.type] then
+    for _, listener in ipairs(EventManager._listeners[event.type]) do
+      listener(event)
+    end
+  end
+end
+
+---@param event Event
+---@param listener fun(...)
+function EventManager.listen(event, listener)
+  if not EventManager._listeners[event.type] then
+    EventManager._listeners[event.type] = {}
+  end
+  if not vim.tbl_contains(EventManager._listeners[event.type], listener) then
+    table.insert(EventManager._listeners[event.type], listener)
+  end
+end
+
+function EventManager.init()
+  if EventManager.initialized then
+    return
+  end
+  for event, listeners in pairs(Listeners) do
+    for _, listener in ipairs(listeners) do
+      EventManager.listen(event, listener)
+    end
+  end
+  EventManager.initialized = true
+  return EventManager
+end
+
+return EventManager

lua/orgmode/events/listeners/align_tags.lua

@@ -0,0 +1,4 @@
+---@param event TodoChangedEvent | HeadlineDemotedEvent | HeadlinePromotedEvent
+return function(event)
+  event.headline:align_tags()
+end

lua/orgmode/events/listeners/init.lua

@@ -0,0 +1,14 @@
+local Events = require('orgmode.events.types')
+local AlignTags = require('orgmode.events.listeners.align_tags')
+
+return {
+  [Events.TodoChanged] = {
+    AlignTags,
+  },
+  [Events.HeadlineDemoted] = {
+    AlignTags,
+  },
+  [Events.HeadlinePromoted] = {
+    AlignTags,
+  },
+}

lua/orgmode/events/types/headline_demoted_event.lua

@@ -0,0 +1,23 @@
+---@class HeadlineDemotedEvent: Event
+---@field type string
+---@field section Section
+---@field headline Headline
+---@field old_headline? string
+
+local HeadlineDemotedEvent = {
+  type = 'orgmode.headline_demoted',
+}
+
+---@param section Section
+---@param headline Headline
+---@param old_level number
+function HeadlineDemotedEvent:new(section, headline, old_level)
+  local obj = setmetatable({}, self)
+  self.__index = self
+  obj.section = section
+  obj.headline = headline
+  obj.old_level = old_level
+  return obj
+end
+
+return HeadlineDemotedEvent

lua/orgmode/events/types/headline_promoted_event.lua

@@ -0,0 +1,23 @@
+---@class HeadlinePromotedEvent: Event
+---@field type string
+---@field section Section
+---@field headline Headline
+---@field old_headline? string
+
+local HeadlinePromotedEvent = {
+  type = 'orgmode.headline_promoted',
+}
+
+---@param section Section
+---@param headline Headline
+---@param old_level number
+function HeadlinePromotedEvent:new(section, headline, old_level)
+  local obj = setmetatable({}, self)
+  self.__index = self
+  obj.section = section
+  obj.headline = headline
+  obj.old_level = old_level
+  return obj
+end
+
+return HeadlinePromotedEvent

lua/orgmode/events/types/init.lua

@@ -0,0 +1,8 @@
+---@class Event
+---@field type string
+
+return {
+  TodoChanged = require('orgmode.events.types.todo_changed_event'),
+  HeadlinePromoted = require('orgmode.events.types.headline_promoted_event'),
+  HeadlineDemoted = require('orgmode.events.types.headline_demoted_event'),
+}

lua/orgmode/events/types/todo_changed_event.lua

@@ -0,0 +1,25 @@
+---@class TodoChangedEvent: Event
+---@field type string
+---@field section Section
+---@field headline Headline
+---@field old_todo_state? string
+---@field is_done? boolean
+local TodoChangedEvent = {
+  type = 'orgmode.todo_changed',
+}
+
+---@param section Section
+---@param headline Headline
+---@param old_todo_state? string
+---@param is_done? string
+function TodoChangedEvent:new(section, headline, old_todo_state, is_done)
+  local obj = setmetatable({}, self)
+  self.__index = self
+  obj.section = section
+  obj.headline = headline
+  obj.old_todo_state = old_todo_state
+  obj.is_done = is_done
+  return obj
+end
+
+return TodoChangedEvent

lua/orgmode/init.lua

@@ -25,6 +25,7 @@ function Org:init()
     return
   end
   require('orgmode.colors.custom_highlighter').setup()
+  require('orgmode.events').init()
   self.files = require('orgmode.parser.files').new()
   self.agenda = require('orgmode.agenda'):new()
   self.capture = require('orgmode.capture'):new()

lua/orgmode/org/mappings.lua

@@ -12,6 +12,8 @@ local ts_utils = require('nvim-treesitter.ts_utils')
 local utils = require('orgmode.utils')
 local ts_org = require('orgmode.treesitter')
 local ts_table = require('orgmode.treesitter.table')
+local EventManager = require('orgmode.events')
+local events = EventManager.event
 
 ---@class OrgMappings
 ---@field capture Capture
@@ -381,10 +383,18 @@ function OrgMappings:_todo_change_state(direction)
     return
   end
   local item = Files.get_closest_headline()
-  if not item:is_done() and not was_done then
+
+  local dispatchEvent = function()
+    EventManager.dispatch(
+      events.TodoChanged:new(Files.get_closest_headline(), ts_org.closest_headline(), old_state, was_done)
+    )
     return item
   end
 
+  if not item:is_done() and not was_done then
+    return dispatchEvent()
+  end
+
   local repeater_dates = item:get_repeater_dates()
   if #repeater_dates == 0 then
     local log_time = config.org_log_done == 'time'
@@ -394,7 +404,7 @@ function OrgMappings:_todo_change_state(direction)
     if log_time and not item:is_done() and was_done then
       headline:remove_closed_date()
     end
-    return item
+    return dispatchEvent()
   end
 
   for _, date in ipairs(repeater_dates) do
@@ -408,31 +418,36 @@ function OrgMappings:_todo_change_state(direction)
   local data = item:add_properties({ LAST_REPEAT = '[' .. Date.now():to_string() .. ']' })
   if data.is_new then
     vim.fn.append(data.end_line, data.indent .. state_change)
-    return item
+    return dispatchEvent()
   end
   item = Files.get_closest_headline()
 
   if item.properties.valid then
     vim.fn.append(item.properties.range.end_line, data.indent .. state_change)
   end
+  dispatchEvent()
 end
 
 function OrgMappings:do_promote(whole_subtree)
   local item = Files.get_closest_headline()
+  local old_level = item.level
   local foldclosed = vim.fn.foldclosed('.')
   item:promote(1, whole_subtree)
   if foldclosed > -1 and vim.fn.foldclosed('.') == -1 then
     vim.cmd([[norm!zc]])
   end
+  EventManager.dispatch(events.HeadlinePromoted:new(Files.get_closest_headline(), ts_org.closest_headline(), old_level))
 end
 
 function OrgMappings:do_demote(whole_subtree)
   local item = Files.get_closest_headline()
+  local old_level = item.level
   local foldclosed = vim.fn.foldclosed('.')
   item:demote(1, whole_subtree)
   if foldclosed > -1 and vim.fn.foldclosed('.') == -1 then
     vim.cmd([[norm!zc]])
   end
+  EventManager.dispatch(events.HeadlineDemoted:new(Files.get_closest_headline(), ts_org.closest_headline(), old_level))
 end
 
 function OrgMappings:org_return()

tests/plenary/ui/mappings_spec.lua

@@ -353,7 +353,10 @@ describe('Mappings', function()
     vim.fn.cursor(5, 1)
     assert.are.same('** TODO [#A] Test orgmode level 2 :PRIVATE:', vim.fn.getline('.'))
     vim.cmd([[norm <<]])
-    assert.are.same('* TODO [#A] Test orgmode level 2 :PRIVATE:', vim.fn.getline('.'))
+    assert.are.same(
+      '* TODO [#A] Test orgmode level 2                                       :PRIVATE:',
+      vim.fn.getline('.')
+    )
   end)
 
   it('should promote the heading and its subtree (org_promote_subtree)', function()
@@ -383,7 +386,7 @@ describe('Mappings', function()
     assert.are.same({
       '* TODO Test orgmode',
       '  DEADLINE: <2021-07-21 Wed 22:02>',
-      '* TODO [#A] Test orgmode level 2 :PRIVATE:',
+      '* TODO [#A] Test orgmode level 2                                       :PRIVATE:',
       'Some content for level 2',
       '** NEXT [#1] Level 3',
       'Content Level 3',